Trussed track



Aug. 19, 1947. H. Y. LAW 2,426,032

TRUSSBD TRACK Filed June 7, 1943 3 Sheets-Sheet 1 mvzmon Jiarry XLa w Al I ORNEYS Aug. 19, 1947.

H. Y. v LAW RUSSED ACK Patented Aug. 19, 1947 UNITED STATES PATENT OFFICE TRUSSED TRACK Harry Y. Law, Merced, Calif.

Application June '1, 1943, Serial No. 489,910

8 Claims. 1

This invention relates to vehicular endless track units, my principal object being to provide a track structure, comprising a plurality of links as usual, in which the links are so constructed and arranged with each other that they are positively locked against breaking upwardly from a straight-line position, without in any way interfering with their flexing in the opposite direction or when passing about the end sprocket wheels. The arrangement is such that the connecting pins of the links are relieved of all strains except those had by the straight-line pull or pressure. link pins or their bushings, making for smooth or relatively noiseless operation over a long period of time. In any event the link locking device functions effectively irrespective of any wear and relative looseness at the link pins,

A further object of the invention is to produce a simple and inexpensive device, and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusal of the followin specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure 1 is a side elevation of one form of my improved endless track unit.

Figure 2 is an enlarged fragmentary elevation, partly in section, of the track linkage detached.

Figure 3 is a plan view of a pair of connected links.

Figure 4 is a fragmentary transverse section on the line d4 of Fig. 1.

Figure 5 is a fragmentary side elevation of a modified form of track unit.

Referring now more particularly to the characters of reference on the drawings, and particularly at present to Figs. 1 to 4, the track links, which are the essential features .of the invention, each comprise a shoe I having a transverse cleat 2 on one end. A central pin boss 3 is formed with and inwardly from the shoe at said one end, and

transversely spaced bosses 4 are disposed in a Similar position on the opposite end of the shoe to receive the boss 3 of an adjacent link therebetween. Link pins 5 swivelly connect corresponding bosses.

Longitudinally extending webbing 6, disposed in a plane at right angles to the shoe, extends and connects the bosses radially inward thereof. The webbing at the boss 3 is in the form of a central Web element 1, while at the opposite end This tends to reduce the wear on the it is in the form of transversely spaced or forked elements 8. The webbing terminates in a flat longitudinal surface 9 which forms a roller engaging track parallel to the shoe, and-the major portion of which is the same width as the boss 3. Over said boss, however, the surface is in the form of a central tongue l0 narrower than said boss, said tongue terminating in abrupt shoulder H at the junction with the wider portion of the surface. Beyond the shoulders said surface 9 is forked to provide a slot I2 therebetween to receive the tongue of an adjacent link; the width of this slot being the same as the spacing between the web elements 8. A transverse pin it is secured in the web element 1 adjacent the outer end of the tongue and projects laterally beyond opposite sides thereof; while a similarly disposed pin I4 is secured in the web elements 8 and extends across the slot l2. Both pins lie in a plane parallel to the link pin centers radially inward thereof but outwardly of the track 9, as clearly shown in Fig. 2, and are considerably farther apart than the bosses and link pins, but symmetrically positioned relative thereto, The bosses 15 in which the pins I3 and M are mounted are the same width as the corresponding portions of the track 9 and merge into the same with a curve, as shown. Formed along the outer edge of the webbing 6 under the track and between the bosses 3 and 4 are saddles l6 and ll, to receive the pins [3 and M respectively of adjacent links, and facing the shoe. These saddles are positioned to seat the pins when the links are in straight alinement with each other, the open end of the saddles flaring, as at l8, so as to guide the pins into seating position, if necessary, irrespective of any wear and consequent relative looseness at the link pins 5.

The above pin and saddle arrangement requires that each pin and the saddle adjacent thereto shall be on the same circle whose center is the center of the adjacent link pin boss, as clearly shown in Figs. 1 and 2.

The supporting structure about which the endless track linkage extends comprises pairs of sprocket wheels l9 spaced to engage the bosses 4. Each wheel has an uneven number of teeth 20, forming boss-engaging sockets therebetween and spaced one-half the distance between adjacent link pins 5. This arrangement provides for successivealternate engagement of the teeth with the bosses so that the wear will be distributed gradually over all the teeth and longer life is assured. The sprocket wheels are mounted in' suitable longitudinal frames 2| disposed between the pairs of wheels, and track engaging rollers 22 are turnably mounted between the frames ad jacent each pair of sprocket wheels on centers spaced from the wheel centers a distance equal to the length of a'link between its pin centers. These rollers assure of straight line movement of the linkage between the. end sprockets, or so that the link pins lie in a line projected between and tangent to the pitch diameter of the sprocket wheels.

Itis to be noted that the diameter of the sprocket wheels and the number of teeth thereon are in..such proportion to the pitch length of the links and tothe size of rollers 22 that sprockets of fifteen teeth (one-half of which are effective at any one time) will cooperate with linkage of a corresponding pitch length to enable a single roller 22 to contact both track surfaces of upper and lower links of the endless track.

It will also be noted that in Fig. 1 I have shown an odd number of links in the endless track, together with sprockets having an odd number of teeth, in order to show the relative positions of the links in the various positions they would successively occupy when in motion.

In the structure shown in Fig. 5, the general arrangement and construction of the links, and the locking or trussing action, is the same as above described. However, the sprocket wheels "a, instead of engaging the pin bosses 4a of the links L, here engage pins 23 projecting laterally from the link webbing 6a centrally between the end bosses and inwardly thereof. This arrangement permits of a much smaller sprocket wheel than is otherwise the case. In order to prevent possible rocking of the links about the pins 23, when fully engaged with and passing about the sprocket wheels, the shoulders Ila of the tracks 90 form stops then engaging the relatively narrow portions of adjacent links, as shown.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the' present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described my invention, what I claim as newand, useful and desire to secure by Letters Patent is:

1. An endless track unit comprising a plurality of links; each link comprising a shoe, a pair of connecting-pin bosses on the shoe at one end spaced transversely and a central pin-boss at the other end, webbing connecting the bosses inwardly of and spaced from the shoe, the webbing at one end being transversely forked over said bosses and extending lengthwise of the link beyond the bosses and at the other end being centrally of the central boss and extending lengthwise of the link beyond said boss, to form a tongue fitting the forked portion of an adjacent link, a transverse pin fixed in the webbing at the outer end of the forked position, a transverse pin projecting from both sides of the tongue at its outer end, and pin-seating saddles formed in the webbing in facing relation to the shoe in position to receive the corresponding transverse pins of adjacent links when said links are in straight-line position.

2. An endless track structure comprising links 4 a each having a central boss at one end and transversely spaced bosses at the-other end to receive the central boss of an adjacent link therebetween, pivot pins connecting corresponding bosses, webbing extending between and inwardly of the bosses, said webbing being forked over the spaced bosses, a rail, extendin along the inner edge of the webbing and likewise forked over the spaced bosses the outer face of the rail being smooth and uninterrupted from end to end and the rails on adjacent links lying end to end when the link are in straight line po ition whereby to form a continuous uninterrupted rail surface along the connected links. I

3. An endless track structure comprising a plurality of separate links, means pivotally connecting the links, interlocking means between the links to prevent flexing of the ground engaging portion of the track between the members in an upward direction, and means forming a substantially continuous rail surface on the links along said portion of the track and above the interlocking means.

4. An endless track structure, such structure comprising a plurality of links, means pivoting the links together at adjacent ends, a member on each link adapted for engagement by a driving element, and co-operating stop elements on adjacent links adapted for engagement with each other when the links are flexed at a predetermined angle to each other.

5. An endless track unit made up of a series of links disposed in end to end relation, each link comprising a shoe, the shoes of adjacent link being pivotally connected together, webbing spaced from and connected with each shoe, the webbing being longer than the shoe and being so shaped at the ends that adjacent ends of the webbing on connected shoes will overlap in side by side rela- 40 tion, a pin on each outer end of the webbing, a

pair of saddles on the inner face of the webbing, such saddles being so positioned that the pin at the end of one link will seat in one of the saddles on the link to which said one link is connected, when the links are in relative straight line position.

6. An endless track unit made up of a series of links disposed in end to end relation, each link comprising a shoe, the shoes of adjacent links being pivotally connected together, webbing spaced from and connected with each shoe the webbing being longer than the shoe and being so shaped at the ends that adjacent ends of the webbing on connected shoes will overlap in side by side relation whereby to provide a continuous track rail parallel to the shoes, a pin on each outer end of the webbing, such pins lying in a plane which is inward of and parallel to the track rail, a pair of saddles on the inner face of the webbing, such saddles being so positioned that the pin at the end of one link will seat in one of the saddles on the link to which said one link is connected, when the links are in relative straight line position.

7. An endless track unit comprising a plurality of links, means pivoting the links at adjacent ends for outward bending movement of the track unit, a pair of laterally projecting spaced apart pins on each link disposed symmetrically with the pivot means, saddles on each link positioned to receive and seat the pins on adjacent links when the links are in a relative straight line position, the open faces of said saddles lying in a plane parallel to the longitudinal axis of the link 5 and between the inner and outer sides of the REFERENCES CITED link. The following references are of record in the 8. An endless track comprising a plurality of file of this patent; links, each link having end connecting-pin bosses, a pair of laterally projecting spaced apart pins 5 UNITED STATES PATENTS lying inwardly of the bosses, a pair of saddles po- Number Name D t sitioned to receive and seat the pins on adjacent 6 arr s Dec. 19, 1922 links when the links are in a relative straight line 5 3 y Ja 5, 9 position, the open faces of the saddles lying in a. 10 15,870 sqhmldt y 1, 1924 plane parallel to the longitudinal axis of the link, 1591730 Wlck July 1926 and the axis of each pin and of the adjacent 1'637777 Law 1927 saddle lying in the arc of a circle centered at the FOREIGN PATENTS adjacent Number Country Date HARRY Y. LAW. 15 752,920 France July 31, 1933 

